Developer for the positive diazotype-process containing a borate, a polyhydroxy alcohol, and a coupler component



Patented Get. .27, 1953 UNITED STATES PATENT OFFICE Franciscus Anthonius Hubertus Kessels, Venlo, Netherlands, assignor to Chemische Fabriek L. van der Grinten, a company of the Netherlands No Drawing. Application July 14, 1948, Serial No. 38,759. In the Netherlands July 14, 1947 18 Claims.

This invention relates to an improved devel oper, in solid form or in the form of a solution, for the positive diazotype-process.

As is Well known a developer is used in this art to bring about the coupling reaction of the diazo-compound and an azo-coupling compo nent (formation of an azodyestufi) by buffering the acid present or formed by this reaction.

The light sensitive diazocompound is located in the photoactive surface or layer of the diazo material; in the present case the azo coupling component is a constituent of the developer. Consequently, the developer, apart from its buffering function, has also the function of supplying the azo coupling component to the photoin modern developing machines-development is performed with a restricted quantity of developer (5-12 grammes per sq. metre), higher concentrations must be used. When using developers having a higher concentration of borax the difficulty is often experienced, however, that 3 they, e. g. in consequence of evaporation in the developing machine, form crystal crusts which sometimes can only with difiicult be re-dissolved and which cause troubles.

For this reason, in practice mostly sodium carbonate, sometimes combined with small quantities of borax, benzoate or acetate, etc., is used.

It has also been proposed to use developers containing a borate together with a tartrate. A tartrate, however, is not capable of solving the solubility problem of borates in diazotype processes. When used in a small amount it does not increase the solubility of borates to a sufficient degree. When used in higher concentration it has a tendency of discolouring the prints.

It has; now been found that such developers for diazotype processes show distinct advantages when they contain, together with an ace coupling component, an alkali borate and a water soluble organic polyhydroxyl compound having in the molecule at least three alcoholic hydroxyl groups attached to adjacent carbon atoms and which enhances the solubility of the borate in a developing medium. Especially suitable alkali borates are potassium borates. 7

It is believed that the alkali borate and the organic polyhydroxyl compound form a borocomplex which, in the medium of the dissolved developer, is more soluble than the equivalent amount of the borate alone would be.

Suitable polyhydroxyl compounds are e. g. mannitol, dulcitol, sorbitol, dextrose, glycerol, cane sugar, gluconic acid, saccharic acid, dextrin, and many others.

The developers according to the invention exhibit attractive properties in practice, more particularly with regard to the difficulties caused by: crystallization, redissolving crystals, hard water used in making the solutions of the developer and the like. More particularly, in developers the louder capacity of which is obtained to a considerable extent, e. g. from 50 to by the use of an alkali borate and the aqueous solution of which consequently must be particularly concentrated with regard to the alkali borate, the polyhydroxyl compounds show good activity. Likewise in developers containing salts, particularly thiosulphates (which are advantageously used therein) in addition to an alkali borate, the activity of the polyhydroxyl compounds has been shown to be considerable.

The polyhydroxyl compounds do not cause any serious reduction (at any rate not to an extent inconvenient in-practice) of the developing capacity of the developers in diazotype processes.

The keeping qualit of the developers according to the invention is enhanced by the addition of hydroquinone-sulphonic acids or their salts.

The polyhydroxyl compounds naturally should be so selected that they give no detrimental reactions with other constituents of the developer, e. g. with the azo coupling component (this e. g. would occur in a combination: glucose-alkali boratephloroglucinol) or have no other inconvenient properties like e. g. a colour or smell; nor should they indirectly cause such inconveniences.

The developers according to the invention, particularly if they derive their bufl'er capacity to a considerable extent from the alkali borate, show amongst other advantages the advantage over carbonate developers that they do not cause serious staining in spots caused by a local excess of developer; in comparison with acetate or benzoate developers and the like they have the advantage that the developed diazotype prints show less discoloration. In general it can be said that they hardly attack the sizing of the papers used.

The developers according to the invention are preferably marketed in the form of a mixture of solids; in this case the polyhydroxyl compound iiis preferably a solid or capable of being solidi- Since the developer contains an azo-coupling component, it may be preferable to divide the 3 mixture constituting the solid components of the developer into parts forming together the complete developer, and to keep these parts separated one from the other until they are dissolved.

In the following examples developers according to the invention are described which are suitable for the development of, for example, the following diazotype papers.

Diazotype paper A.Base paper of 110 gms. per sq. metre is coated with approximately 8 gms. per sq. metre of the following aqueous solution:

2.5% chlorostannate of paradiazodiethylaniline 1% alum 2% thiourea 2% ammonium oxalate 0.1% gelatine and dried.

Diazotype paper B.-Base paper of 110 gms. per sq. metre is coated with approximately 3 gms. per sq. metre of the following aqueous solution:

1.6% nitrate of paradiazoethylbenzylaniline 1% alum 2% ammonium oxalate 0.1% gelatine and dried.

Diazotype paper C.-Base paper of 110 gms. per sq. metre is coated with approximately 8 gms. per sq. metre of the following solution:

1 chloride of paradiazodiphenylamine 1% alum 2% thiourea 2% ammonium oxalate 0.1% gelatine and dried.

Diaeotype paper D.--Base paper of 110 gms. per sq. metre is coated with approximately 12 gms. per sq. metre of the following solution:

3% zinc chloride double salt of l-diazo--diethylamino-3-chlorobenzene 2.5% tartaric acid 1.5% sodium salt of 1,3,6-naphthalene=trisulphonic acid 1.5% ammonium sulphate 0.3% gelatine and dried.

Dz'aeotype paper E.Base paper of 110 gms. per sq. metre is coated with approximately 12 gms. per sq. metre of the following solution:

1.5% chlorostannate of l-diazo-l-(ethyl-benzoyl) amino-2-5-diethoxybenzene 1% alum 1% boric acid 2% sodium salt of 1,3,6-naphthalene-trisulphonic acid 3% thiourea 0.1% gelatine and dried.

Example 1 Developer in liquid form ready for use:

130 gms. borax 100 cu. cm. glycerol 8 gms. resorcinol 2 gms. sodium salt of isopropylnaphthalenesulphonic acid 1000 gms. water This developer develops adequately when 9 gms. per sq. metre of it is applied to a print on diazotype paper D. A brown picture is obtained. The developer can be evaporated to one-third of its original volume without crystallization occurring. It does not cause inconvenient stains by local excess and causes less discoloration of the diazotype copy than corresponding developers with acetate, benzoate or phosphate would do.

Example 2 Developing powder:

gms. borax 50 gms. dextrose 20 gms. sodium thiosulphate 10 gms. orcinol 20 gms. thiourea 1 gm. sodium salt of isopropylnaphthalene-sulphonic acid Upon dissolving this powder in 1000 gms. of water a developer is obtained for the development of prints on diazotype paper 13 with 12 gms. per sq. metre (colour of prints: brown). The solution can be evaporated to one third of its volume without showing crystallization. Crusts formed upon drying will re-dissolve readily in fresh developer. It will not cause staining by local excess and it causes less discoloration of the diazotype copy than a developer containing an acetate, benzoate or phosphate.

Example 3 A cardboard container is filled with the following constituents:

When the entire contents of the container are dissolved in 1000 gms. of water a developer is obtained for developing prints on diazotype pa per A with 9 gms. per sq. metre (colour of prints: black). This developer can be evaporated to one third of its volume without formation of crystals occurring. Crystals formed on drying of the developer readily redissolve in fresh developer. No inconvenient stains, less discoloration than with acetate, benzoate or phosphate developers. The keeping quality is considerably better than that of a corresponding developer with sodium carbonate.

Example 4 Developing powder:

110 gms. potassium tetraborate 5H2O gms. cane sugar 8 gms. phloroglucinol 8 gms. resorcinol 25 gms. thiourea 2.5 gms. sodium salt of isopropylnaphthalenesulphonic acid.

When this powder is dissolved in 1000 gms. of Water a developer is obtained for developing prints on diazotype paper B with 9 gms. per sq. metre (colour of prints: black). The solubility is considerably better than that of a corresponding developer without cane sugar. No inconvenient stains; discoloration less than with acetate, benzoate or phosphate developers.

Example Developing powder:

60 gms. borax 89 gms. dextrin 6 gms. hydroxyethylamide of betahydroxy-naphthoic acid 6 gms. resorcinol 1 gm. potassium salt of hydroquinone monosulphonic acid 1 gm. sodium salt of isopropylnaphthalene-sulphonic acid If this powder is dissolved in 1000 gms. of water a developer is obtained for the development of prints on diazotype paper C with 12 gms. per sq. metre. The powder is readily soluble. No inconvenient stains; discoloration less than with acetate, benzoate or phosphate developers; only little attacking of the sizing of the paper.

Example 6 Cardboard container filled with:

If the contents of the container are dissolved in 1000 gms. of water a developer is obtained for the development of prints on diazotype paper B with 9 gms. per sq. metre (black). ,It can be evaporated to one third of its volume without formation of crystals. When it is evaporated completely the crystals then formed readily redissolve in fresh developer. N o stains; discoloration less than with acetate, benzoate or phosphate developers.

Example 7 Developing powder:

50 gms. borax 25 gms. sodium carbonate 20 gms. thiourea 8 gms. phloroglucinol 8 gms. resorcinol 30 gms. mannitol 1 gm. potassium salt of hydroquinone monosulphonic acid 2 gms. sodium salt of isopropylnaphthalenesulphonic acid If this powder is dissolved in 1000 gms. of water a developer is obtained for developing prints on diazotype paper A with 9 gms. per sq. metre (black). Less staining than with corresponding developer of the same bufier capacity but containing only sodium carbonate. Discoloration less than with acetate, benzoate or phosphate developers. The developer can be evaporated to 40% of its volume without crystallization.

6 Example 8 Developer in liquid form ready for usei 110 gms. potassium tetraborate 5H2O 50 on. em. lactic acid (100%) 10 gms. phloroglucinol 100 gms. mannitol 1 gm. isopropylnaphthalene-sulphonic acid 1000 gms. water This developer develops prints on diazotype paper F with 12 gms. per sq. metre in a violet colour. It does not cause inconvenient stains by local excess and gives less discoloration of the diazotype copy than when a corresponding developer is used which contains instead of the borate an acetate or lactate. This developer may be evaporated to approximately 40% of its volume without crystallization.

What I claim is:

l. A developer for positive diazotype material, comprising an alkali metal borate as the principal buffering component, an azo coupling component comprising a substance from the group consisting of phloroglucinol and hydroxyethylamide of betahydroxy-naphthoic acid, and a content of an organic polyhydroxyl compound that solubilizes the borate, said compound having in its molecule at least three alcoholic hydroxy groups attached to adjacent carbon atoms.

2. A developer for positive diazotype material, comprising an azo coupling component, an alkali metal borate as the principal buffering component, a thiosulfate, and a content of an organic polyhydroxyl compound that solubilizes the borate, said compound having in its molecule at least three alcoholic hydroxyl groups attached to adjacent carbon atoms.

3. A developer for positive diazotype material, comprising an azo coupling component, comprising a substance from the group consisting of phloroglucinol and hydroxyethylamide of betahydroxy-naphthoic acid, a potassium borate as the principal buffering component, and a boratesolubilizing organic polyhydroxyl compound having in its molecule at least three alcoholic hydroXyl groups attached to adjacent carbon atoms.

4. A developer for positive diazotype material, comprising an azo coupling component, an alkali metal borate as the principal bufiering component, a content of an organic poly-hydroxyl compound that solubilizes the borate, said compound having in its molecule at least three alcoholic hydroxyl groups attached to adjacent carbon atoms, and a substance from the group consisting of hydroquinone sulfonic acid and salts thereof.

5. A developer for positive diazotype material, which is entirely soluble in an aqueous developing medium at a concentration effective to develop the material when applied as a thin liquid film and which comprises an azo coupling component, comprising a substance from the group consisting of phloroglucinol and hydroxyethylamide of betahydroxy-naphthoic acid, a potassium borate as the principal buiiering component, potassium carbonate as a minor bufiering component, and a content of an organic polyhydroxyl compound that enhances the solubility of the potassium borate, said compound having in its molecule at least three alcholic hydroxyl groups attached to adjacent carbon atoms.

6. A developer for positive diazotype material, comprising an azo coupling component, an alkali metal borate as the principal bufiering component and an alcohol having six hydroxyl groups 2 at six adjacent carbon atoms to solubilize the borate.

7. A developer for positive diazotype material, comprising an azo coupling component, an alkali metal borate as a buffer and mannitol to solubilize the borate.

8. A developer for positive diazotype material, comprising an azo coupling component, an alkali metal borate as a buffer and sorbitol to solubilize the borate.

9. A developer for positive diazotype material, comprising an azo coupling component, comprising a substance from the group consisting of phloroglucinol and hydroxyethylamide of betahy'droxy-naphthoic acid, anv alkali metal borate as the principal bufiieringcomponent and a borate-sclubilizing content of a Water-soluble carbohydrate having in its molecule at least three alcoholic hydroxyl groups attached to adjacent carbon atoms.

10. A developer for positive diazotype material, comprising an azo coupling component, comprising a substance from the group consisting of phloroglucinol and hydroxyethylamide of betahydroxy-naphthoic acid, an alkali metal borate as the principal buffering component and a borate-solubilizing content of a hexose.

11. A developer for positive di'azotype material, comprising a potassium borate as the principal buffering component, a borate-solubilizing content of a water-soluble carbohydrate having in its molecule at least three alcoholic hydroxyl groups attached to adjacent carbon atoms, and an azo coupling component comprising a substance from the group consisting of phloroglucinol and hydroxyethylamicle of betahydroxy-naphthoic acid.

12. A developer for positive diazotype material, comprising a potassium borate as the principal buifering component, av borate-solubilizing content of an alcohol having six hydroxyl groups at six adjacent carbon atoms, and an azo coupling component.

13. A developer for positive diazotype material, comprising an azo coupling component, a potassium borate as the principal buffering component, a borate-solubilizing content of an alcohol having six hydroxyl groups at six adjacent carbon atoms, and a substance from the group consisting of hydroquinone sulfonic acid and salts thereof.

1 1. A developer for positive diazotype material, comprising a potassium borate as the principal buffering component, a borate-solubilizing content of an alcohol having six hydroxyl groups at six adiacent carbon atoms, an 320 coupling component, a potassium salt of hydroquinone sulfonic acid, and potassium thiosulfate.

15. A packaged Water-soluble developer in powder form for positive diazotype material, composed of a plurality of portions including in one alkaline reacting buffer substance consisting principally of a potassium borate, and in another portion on azo coupling component and a boratesolubilizing content of an alcohol having six hydroxyl groups at six. adjacent carbon, atoms.

16:. Apackaged Water-soluble developer in powder form for positive diazotype material, composed of a plurality of portions-including in one portion alkaline reacting substance consisting principally of alkali metal borate, and in another portion an azo coupling component. comprising a substance from the group consisting of phloroglucinol and hydroxyethylamide of betahydroxynaphthoic acid together with a borate-solubiliaing content of an organic polyhydroxyl compound having in its molecule at least three alcoholic hydroxyl groups attached to adjacent carbon atoms. 7

17. A developer for positive diazotype material comprising alkali metal borate including a sodium borate as the principal alkaline reacting component, an azo coupling component comprising a substance. from the group consisting of phloroglucinol and hydroxyethylamide of betahydroxynaphthoic acid, and a borate-solubilizing content of an organic polyhydroxyl compound having in its. molecule, at least three alcoholic hydroxyl groups attached to adjacent carbon atoms.

18. A developer for positive diazotype material, comprising alkali metal borate as the principal bufiering component, an azo coupling component comprising phloroglucinol, and a borate-solubilizing content of an organic polyhydroxy compound having in its molecule at least three alcoholic hydroxyl groups attached to adjacent carbon atoms.

FRANCISCUS ANTHONIUS HUBERTUS KESSELS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,837,679 Schmidt et al. Dec. 22, 1931 1,841,653 Van Der Grinten et a1. Jan. 19, 1932 1,990,800 Russel Feb. 12, 1935 2,197,016 Wood, Apr. 16, 1940 OTHER REFERENCES Pharmaceutical Formulas, publ. by Chemist and Druggi'st, London, 1944, vol. 1, pages 26, 59-61, 64, 205, 209, 350, 351, 356 and 415.

Pharmaceutical Recipe Book, publ. by American Pharmaceutical Association, 3rd Ed, 1943, page 210.

Saunders: The Aromatic Diazo Compounds, publ. by Edward Arnold and Co., London, 2nd Ed, 1949, pp. 199 and 348.

Henney et al.: Handbook of Photography, McGraw-Hill Book Company, New York, 1939, pages 337 to 339 cited.

Kolthofi et al.: Textbook of Quantitative Inorganic Analysis, MacMillan Company, New York, Sept. 1943, pages 560 and 561.

Mellorr, Comprehensive Treatise on Inorganic and Theoretical Chemistry, London, 1924-, vol. 5, pages 74 and 75,. 

1. A DEVELOPER FOR POSITIVE DIAZOTYPE MATERIAL, COMPRISING AN ALKALI METAL BORATE AS THE PRINCIPAL BUFFERING COMPONENT, AN AZO COUPLING COMPONENT COMPRISING A SUBSTANCE FROM THE GROUP CONSISTING OF PHLOROGLUCINOL AND HYDROXYETHYLAMIDE OF BETAHYDROXY-NAPHTHOIC ACID, AND A CONTENT OF AN ORGANIC POLYHYDROXYL CO MPOUND THAT SOLUBILIZES THE BORATE, SAID COMPOUND HAVING IN ITS MOLECULE AT LEAST THREE ALCOHOLIC HYDROXY GROUPS ATTACHED TO ADJACENT CARBON ATOMS. 